My son is turning 4 next week. My husbands sil has just messaged to ask if my 14 year old nephew can bring his girlfriend to my sons party at our house. There is only going to be me (mum), husband (dad), daughter (8 year old) (sister), both sets of grandparents and my husbands brother, wife (sil) and two sons (14 and 9 year old). Not even husband, or grandparents have met this girlfriend before. I just find it weird that this is the time we should meet her. So am I unreasonable to say no. Or should I let her come. Son absolutely adores and idolises 14 year old nephew and would hugely miss him if he didn’t come. Told this is only time nephew can see girlfriend as she lives 2 hrs away and so only see each other once a month for a weekend.