Nigerian man declares intention to marry his mother-in-law two years after his wife’s death

“A man (name withheld) lost his wife after they had had three children (two boys and a girl). His wife died at 34 years old. Two years after, he wants to marry his mother-in-law who is 57 years old and a widow. He is 46 years old. He says he does not need more children nor want to marry an outsider who may isolate and maltreat his children. Some members of their two wider families support the idea while many are against it. Is this right?” he wrote.