Grandma sends bill after granddaughter visits.

Dear Amy: I sent a check for $300 to my mother to cover my daughter's expenses during her visit. Upon my daughter's return, my mother sent me an invoice for $475.50 for additional expenses, including the cost of gas to and from the airport to transport her, train tickets to go to the city to a museum, and the cost of the museum admission. It was an itemized bill.

This is hurtful, as this past winter my mother came to live with us for four months and we paid for everything, including a nice vacation to an island over Christmas.

How do I address her behavior? I am hurt and angry by her decision to charge me for gas to pick up her granddaughter from the airport, as well as the other expenses.

My mother is a single woman — a retired college professor — and we have never asked her to pay for anything. We even write her a check for groceries when she hosts Thanksgiving dinner.

Now I feel she has taken advantage of my generosity and I don't trust her to spend time with my daughter because it is just too costly for me — financially and emotionally. — Burned by Grandma

Dear Burned: You are going to have to express your concern directly to your mother.

Your daughter's trip to see Grammy has cost you (I'm estimating) around $1,000, with plane tickets, plus the invoiced expenses incurred while she was there.

Is your mother financially insecure? Is she worried about maintaining her own lifestyle in retirement? These are legitimate concerns.

But is there a legitimate reason she couldn't stay within the reasonable $300 budget, spending over twice that amount? Is this itemized bill her passive-aggressive way of telling you that she doesn't actually want to host your daughter for such a long visit?

After you communicate your questions and concerns to your mother, you will have to make the tough decision about future visits.

Because your mother seems to communicate through monetizing relationships, you'll simply have to decide whether this relationship between grandmother and granddaughter is one you can afford to foster.

You can write Amy Dickinson at askamy@tribune.com or by mail to: Ask Amy, Chicago Tribune, TT500, 435 N. Michigan Ave., Chicago, IL 60611.