need advice please on step daughter who is stealing

[puresoulexpression]

Hi I am puresoulexpression,
Thank you for taking the time to read this in advance. I am writng in regards to advice that i would love to have. My 15 year old step-daughter is living with my husband and i . Her mother has had her living in her home for the majority of her life but now this is the second time in three years that she is living with us. She has had a lot going ton this time since she moved in. Oh by the way I have an 8 year old daughter with someone else and my hisband and i have a three year old together and I have one other step- daughter who is 18. the two girls 15 and 18 are sisters with same mother and my husband is there father. Any how the 15 year old has started taking my husband and my debit /credit cards for awhile now 10,20,30 here and there. Of course she does this when we have not been looking and we actually have not caught her. But with all of the investigating and putiing the pieces together we know she is doing this. In the past shed to take the familys things but i was never able to say anything my husband wanted 7to handle it which i undeerstand. But nothing was ever really done about it and now she is taking our money. We have not confronted her about this yet but i hope that my husband will want to do this soon.I really am getting tired of this bull . my husbands job is demanding so i am the one doing everything for the kids. doctors appts,friends,going to school, giving them money,taking them to extra curricular things. i am home when friends are here so i am ticked. she also has had some issues maybe with depression. so things are getting overwhelming. any advice i would love it. thanks pure