Wiz Khalifa claims Amber Rose's house is too dirty and unsafe for their son to live in.
The 27-year-old rapper is submitting photographic evidence against the model - who filed for divorce last September amid claims he had cheated on her - as part of his bid to change their custody agreement so he gets more time with their son Sebastian, who turns two on Saturday (21.02.15).
According to TMZ, the photo evidence Wiz is submitting includes a picture of a back patio covered with dog poop, a knife left on a counter top and loose garbage in the yard.
It was previously revealed that Wiz - who hasn't officially made a legal bid to challenge the custody agreement yet - has a number of complaints against his estranged wife, one of which is that the family dog eats its own faeces and is then allowed to lick Sebastian's face.
His allegations also state that Amber often stays out all night, requiring that relatives and staff take over, and when she wakes up she often only spends 15 minutes with the little boy before "disappearing".
In addition, the 31-year-old beauty reportedly engages in a number of "shouting matches and vulgar exchanges" with her mother which upsets Sebastian.
Wiz - whose real name is Cameron Jibril Thomaz - recently blasted Amber as a "foul creature" for "using" Sebastian "against" him.
Responding to a fan who told him to "get your wife back" on Twitter, he initially replied "no thanks" before launching into a tirade.
He wrote: "A woman who would do something to a kid to spite that kids father is a foul creature.
"Seen my boy. All is well.
"that's pretty much the only thing that can spin my universe out of control...Sucks when people try to use that against you but the cool part is figuring out how much self control you have. (sic)"
Wiz admitted seeing his little boy always made him feel better.
He wrote: "As long as he's playing and smiling i'm cool. can't be p***ed when i see that handsome face.
"i tell him everyday that this is all his. (sic)"