“Vanity and pride are different things, though the words are often used synonymously. A person may be proud without being vain. Pride relates more to our opinion of ourselves, vanity to what we would have others think of us.”
— Jane Austen (Pride and Prejudice)
Being proud is acceptable as long as it does not go to the point where one is full of oneself. Celebrate achievements and milestones in a person’s life – no harm in this. Just do not be vain.