Is it permissible for spouses to sleep naked, and does embracing during sleep necessitate ghusl before prayer, or is wudu sufficient?

It is permissible for spouses to see and touch each other's private parts, and the evidence for this is the Almighty's saying: (And those who guard their private parts. Except from their wives or those whom their right hands possess, for indeed, they are not to be blamed). This is also evidenced by the action of the Prophet, peace and blessings be upon him, with Aisha, may Allah be pleased with her, when they bathed together, and his saying, peace and blessings be upon him: "Guard your private parts, except from your wife or what your right hand possesses." If embracing does not lead to ejaculation or intercourse, then ghusl (ritual bath) is not obligatory. If madhy (pre-seminal fluid) is discharged, the man must wash his penis and testicles, and the woman must wash her private parts, and both need only perform ablution.