DR. WALLACE: I'm one of three girls in our family, and I'm the oldest. My younger sisters are 14 and 11. My 14-year-old sister is pretty chill; she doesn't bother me and is respectful of my space. But my 11-year-old sister barges into my room continuously, sometimes when I'm concentrating on my studies and other times when I'm on the phone with one of my close friends or my boyfriend.

It's really uncomfortable when she does this because she doesn't respect my privacy, and she'll just start talking even if I'm on the phone. I was mentioning this to some of my friends at school, and one of them recommended that I make a sign for my door that says "Do Not Enter."

So I went to an arts and craft store, got some materials and made a really nice sign that I put on my bedroom door. But no sooner had I put it in place than my younger sister came barging in within an hour, doing her usual routine of interrupting me.

My mother did raise an eyebrow when she saw my sign, but I explained why I made it and that some of my friends my age have similar signs on their bedrooms to keep their younger siblings out some of the time.

Since my mother is fine with me having this sign, how can I get my little sister to respect it and, more importantly, to not barge in and interrupt me constantly? — She's Disrespectful of My Privacy, via email

SHE'S DISRESPECTFUL OF MY PRIVACY: First, be sure your sign isn't up all the time, just when your door is closed. Also take the time to make a sign for your little sister's room as well! Cut her in on the deal, and give her a privacy sign of her own just like her older sister has. Then agree with her to rules the two of you girls will mutually respect. Make it a rule that there's no opening the door to come in when the door is closed and the sign is up.

Let her know that only a soft knock is allowed, and if the door doesn't open within 10 seconds, that means privacy is to be respected and she should return to her room for at least half an hour before trying again.

Tell her you will respect the rules for her just the same way, especially if she has a friend over to play in her room, for example. Tell her there may also be times when she's reading or doing homework and that you will respect her privacy in the same way.

Be sure to run all this by your mother to make sure she's good with it, and you might want to involve your middle sister as well, as she could be a good ally for you. It might make sense to also get her a sign so that all three of you girls can be equal in terms of your privacy. Finally, be sure to knock on your little sister's door once in a while when her door is closed and her sign is up. Do what you've asked her to do by waiting for 10 seconds to see if she's going to answer it, and if she doesn't, return to your room.

Treating your sister as an equal and giving her the same power of privacy is likely the best way to not only get your point across but gain her compliance.

MY GIRLFRIEND'S BESTIE IS INSUFFERABLE!

DR. WALLACE: As a guy who is a senior in high school, I want to spend time with my girlfriend as much as possible, but I have to compete for her time with her best friend. And her best friend is unfortunately an egotistical, self-centered girl who thinks the world owes her favors each and every day.

I honestly don't see what my girlfriend sees in this friend, but apparently they've known each other for eight or nine years, so I just tolerate this girl. I went by last week to pick up my girlfriend from her house for a date, and this girlfriend of hers was just about to leave, but the girls were talking about some guy who had asked her out on a date. She had the nerve to say that she told the guy to "take a number," as she had a long list of guys who wanted to ask her out.

I was surprised to hear this, so I asked her what this number thing meant. She talked about our main post office where you have to take a number from a little machine and then they call numbers in sequence so that you can come up and bring your packages or whatever to the counter when it's your turn.

Apparently, this is where the idea came from, but I find it to be demeaning and more than arrogant to say that to a guy who just sincerely asked her out on a date. When I was alone with my girlfriend later, I mentioned this to her, but she kind of laughed it off and said that it was just her personality. Do you think this girl was out of line, or am I the one who needs to calm down a bit? — I Find This Girl Insufferable, via email

I FIND THIS GIRL INSUFFERABLE: You're facing a classic case of being in the position to decide which battles you are going to choose to fight or to avoid. Since you and your girlfriend have an excellent relationship, do your best to mitigate any potential friction by staying clear of distractions and difficult conversations that may be centered around your girlfriend's best friend.

Your girlfriend is so close to her that she's going to naturally overlook some of this girl's poor behavior and write it off as frivolous, even though you and I both agree this girl was being quite disrespectful and arrogant toward other people. However, this is a battle you do not want to engage at this stage of your relationship. Carry on and let it go, even though I feel your assessment of the girl's behavior was accurate.

Dr. Robert Wallace welcomes questions from readers. Although he is unable to reply to all of them individually, he will answer as many as possible in this column. Email him at [email protected]. To find out more about Dr. Robert Wallace and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.

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