She struggles to raise her kids because their father is a deadbeat dad.
deadbeat dad
idiomA man, especially one who is divorced or estranged from his partner, who fails to provide monetary child support when he is legally required to do so.
The court ordered him to pay child support, but he remains a deadbeat dad who refuses to contribute a single cent.
Despite his public claims of being a devoted parent, his former partner labeled him a deadbeat dad due to his persistent refusal to provide the legally mandated financial support.