Christina Haack out with children in the middle of custody battle with Ant Anstead

Christina Hack goes all out to prove she’s not the shitty mother, the ex-husband Ant Anstead wants people to believe … sitting on the sidelines of her children’s football games.

Christina was in full football-mom-fashion Saturday and crashed into her portable chair next to her daughter Taylor to see son Brayden on the field. For Christina, it is her first public appearance since Ant requested custody of their son Hudson and tore her motherly skills.

Christina was not only there with her children from her first marriage to Tarek El Moussabut with his parents, they made a day out of it … so Taylor competed in a separate game.

It does not appear that Hudson was there … so he must have been with Dad.

TMZ broke the story … The ant went AF about Christina in legal documents filed Thursday accused her of being an absent mother, endangering Hudson and using the child as a piece on social media.

Christina shot back in his own Friday legal documents and tried to poke holes in Ant’s claims. She told the court that there is no need for an emergency order to give Anstead full custody of the 2-year-old Hudson, and so far the judge agrees.