How do I address this issue?

Every year we chip in at work to buy our boss a gift. This year they decided on a gift that is $40 a person. I cannot afford to chip in this year, so I let them know so they could divide my balance between themselves. My issue is my mom is one of my coworkers and she took it upon herself to pick up my share. I did not mention to her my not paticapating since I did not want her help. Do I say something to her or leave it alone? Do I have to say thank you?




I can answer any questions you may have. I have posted about her before but I can't find it, I'm posting from my phone.


Thanks for your help.