Not in the mothers' club

I go to a 'rappelkiste' every week with Jonna my one year old.  This is basically an indoor playground for toddlers and babies in the basement of a church.  All the mothers and such see me there every week with what they percieve to be my baby.  I'm really not much younger than many of these mothers.  Anyway one of the girls that works there (probably about my age) asked me today if Jonna "ist mein kind?"  (my child).  I said no, but thought about how awkward it would have been if she had been.  Imagine someone asking me that implying that I shouldn't be her mother and I were.  Anyway she told me that they have  all been trying to figure it out.