DEAR ANNIE: My ex-wife, “Daisy,” has custody of our two children. She makes several times my salary, lives in a home where the mortgage and taxes are skyhigh, and has an expensive lifestyle. I live frugally, always pay child support and have visitation rights. Often, my children stand me up when I show up to get them. I’ll get to a birthday party or wedding with just my son and have to tell everyone, “My daughter has a migraine.” The real answer is, “She is lazy and doesn’t want to miss movie night with her friend.” Her mother is spineless. My son also has a fluctuating weight problem because he eats too much junk food. At a recent luncheon, he refused to eat but then demanded a piece of chocolate cake and shoved it down his throat.

Daisy isn’t happy about my not paying that much support and has spoken to the kids about our financial arrangement, which we’d agreed she wouldn’t do.

She wants to throw our daughter a lavish bat mitzvah for her 13th birthday. The total cost would be five figures. I’ve refused to pay it because she doesn’t need it and it would be a financial hardship for me. Also, given her lack of effort at school and refusal to attend family functions, I don’t think her behavior merits a huge reward.

Daisy says that if I refuse to pay, I won’t be invited. However, that would be a problem for me, because it would look horrible if I did not attend. And she says that if I refuse to contribute financially but show up anyway, she’ll have security throw me out.

Should I do what my wife wants and cough up the cash, or should I go to the party and get tossed out the door? I’m saving money religiously, because given Daisy’s lack of control over my daughter, I’m afraid my daughter will get in trouble. — STINGY DAD AND PROUD OF IT

DEAR STINGY DAD: You should do what is in the best interest of your children, and you and your ex-wife should make every effort to be as amicable to each other as possible. Yes, you should pay a customary and reasonable amount for your only daughter’s bat mitzvah.

Your daughter will never turn 13 again. Make it special for her and leave your baggage and negative feelings at the door. As for the constant headaches from your daughter and her blowing you off, remember that you are the parent and she is the child. Ask yourself why she doesn’t want to see you.

Being embarrassed by your son’s behavior might propel you to seek help for him. Let’s hope. The human body, especially a growing boy’s body, does not feel good just eating cake. But being ashamed of him and criticizing his mother don’t do anyone any good.

Be open and honest with them about your finances, and be open and honest with what your wallet and heart can contribute to your daughter’s bat mitzvah.