Photo: Paras Griffin/GC Images; Kim Zolciak-Biermann/Instagram

Kim Zolciakis understanding of her daughters' relationship withKroyBiermann.
On Sunday, older daughters Ariana, 21, and Brielle, 26, honored their mom’s estranged husband onFather’s Day. The former NFL star, 37, adopted her two daughters from previous relationships after marrying Zolciak in November 2011.
A source tells PEOPLE that theReal Housewives of Atlantaalum, 45. is “okay with” Ariana and Brielle continuing their relationship with Biermann amid the former couple’s contentious breakup.
“She understands and is okay with it. She wants them to have a good relationship,” a source tells PEOPLE.
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Ariana Biermann/Instagram

Biermann and Zolciak also share four younger children — 9-year-old twinsKaia Rose and Kane Ren, 10-year-old sonKash KadeandKroy Jagger, 11.
Zolciak and Biermann bothfiled for divorceat the start of May. Since, the divorce has gotten messy, with an apparent custody battle as both parents haveasked for full physical custodyof the children.
Brielle Biermann/Instagram

Biermann and Zolciak are stillliving in the same Georgia homeamid their contentious split, which most recently included the former NFL starasking the court to appoint a Guardian ad Litemfor their minor children.
source: people.com