HELP MEE!!

I only remember a little plot of that story, genre yaoi, so there was a child named "a" he was the illegitimate son of a famous artist, one day he was brought to the artist's house because his mother died, where he met his half-brother, his half-brother I guess had an interest in him, the story here is they still young,I also remember that the biological child of the celebrity just now was an alpha, Alpha is strong but has a very beautiful face as a child, The celebrity's biological child is also younger than the main character, One day this biological boy saw the main character and his father playing together and I think he was jealous, I remember him telling his dad "dad did you forget he was my birthday present" after that I forgot, if you know this manga please tell me the title╥﹏╥