What does a native English speaker understand from each one of these sentences :
His mother loves him His mother likes him
is like only a weak version of love or imply a different meaning ?
In many contexts, love is just an intensive form of like ("I love going to the seaside").
But when we are talking about the emotional bond between people (especially parent and child) they are different in kind, not just in degree.
Liking somebody does not imply that there is any amount of love there.
The reverse is more problematic. It's certainly possible to say (meaningfully and truthfully) "I love her, but I don't like her much at the moment". It's probably rarer to say timelessly "I love her but I don't like her" - but with family members, it must occur sometimes.
So "His mother loves him" and "his mother likes him" are both expected, but neither is necessarily true. "His mother likes him but doesn't love him" seems unlikely, but the other way round is plausible.