Shakespeare married Anne Hathaway when he was 18, in approximately 1582.
Shakespeare was buried inside
Holy Trinity Church beneath a stone slab engraved with his epitaph:
Good friend, for Jesus' sake forbear
To dig the dust enclosed here.
Blessed be the man that spares these stones,
And cursed be he that moves my bones.
In my research, I have not come across anything mentioning a cousin of Shakespeare.