Looking for manga about son who thinks he's his mom

[darkaura]

It's about a single father and his son, the mom passed away. However the son pretends to be his mom in order to comfort his dad. Or maybe it was actually the son who passed away, and the mom was pretending to be her son, I don't remember.

 

[solstice258]

Is it this one? https://mangadex.org/title/af1425e8...father-and-son-will-cross-the-line-in-10-days

If it isn't, I'm gonna be worried why there are multiple manga with this premise ._.