Is it normal ?

Don't change a thing! She and he will get used to it. I would suggest extra foreplay time to get her vagina well lubricated and for him to enter her very, very slowly - I mean VERY slow! That will give her labia and vagina walls time to adapt to his penis. Did she mention if he's very well-endowed? If she has any experience, she should know. Also a small vibrator or dildo might help when they're not having sex. Or during, if they like ;-)

foreplay(warm and wet her up),very slow entry,have sex often

sorry

Her husband sounds like an ass.
to tight, really.
How many guys out there would like to try this woman?

Lubrication, lubrication, lubrication! Either her own natural juices if her husband takes his time before actual intercourse or by using artificial lube.

If she's nervous about sex and he's impatient and ignorant I see huge problems ahead.

Use a vaginal dilator set. Start with the smallest that fits snugly. Work your way up to the largest.