While some click with their step-parents straight away, others want nothing to do with them.
An 18-year-old have been left feeling 'second best' after his mum's fiancé forced him out of his childhood home with his pet dog in tow.
Venting to Reddit, he explained how his soon-to-be step-dad is "severely allergic" to dogs - and wouldn't be able to live in the same house as one.
He said: "My dad died in a work accident when I was aged 15. Dax was my dad’s dog - he rescued him from a shelter when he was still a puppy. We have had him since I was aged 11 so he means a lot to me.
"Last year, my mum started going out with Anthony and they just got engaged. Anthony wanted to move in but the problem is he’s severely allergic to dogs.
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"My mum told me we had to get rid of Dax my dog. It wasn't even as a question - she just straight up said that’s what we’re going to do."
Not wanting to give up his dog, the teen tried to explain to his mum how Dax makes him feel connected to his late dad.
He added: "I fought with my mum over this because he is my family and he is what has helped me get through losing my dad.
"But my mum was like nope he has to go. We fought so much about it I actually cried.
"Nobody wanted to adopt Dax and I had to beg my grandpa from my dad’s side to take him or else my mum was going to take him to a shelter.
"The problem was my grandpa lives an hour away and he can’t do much physical stuff like take him out for walks, feed him or take him to the vets."
Trying to come up with a solution, his grandad suggested he moved in with him since he attends online classes for his schooling.
"I told my mum I want to move in with my grandpa so I can be with Dax," he added. "She got really mad about that and said she and Anthony are my family and I need to be with them.
"I told her Anthony’s not my family. I have my own problems with him - he keeps talking about being my new dad and I don’t like that. He he doesn’t listen when I tell him to stop saying he’s my new dad because he’s not.
"Dax is my family and she made me get rid of him just like that. My grandpa’s my family too anyways."
Going ahead with his plan, the teen moved into his grandad's house a few weeks later.
He added: "My mum is still mad. She’s not going to force me to come back but she’s still saying I’m being a really rubbish son and I’m choosing to be with my dog instead of with them.
"It hurt too much being without him. He was taken to my grandpa’s a week before I left and all that time I was up crying missing him. And I know he missed me too because he lost it when I got there.
"My mum keeps telling me to come back and stop being cruel with her but I’m happy here with my dog. I get she’s got someone new to be happy with and that’s cool, it’s her life, but why can’t I be happy too with my dog living with me?"
While most users agreed the teen should do whatever makes him happy, others slammed his mum and her fiancé for their handling of the entire situation.
One user said: "You are absolutely not a rubbish son. What your mum is doing is horrible. She’s trying to force a new 'family' on you without your consent.
"Stay with your grandpa and keep the dog. Hope things look up for you in the future. I can tell Dax is a good boy."
Another user added: "It’s the forcing a 'new dad' on him that really gets to me. I’m sorry for your loss- go live your best life with Dax."
A third user said: "He doesn't need a 'new dad' - he might need a father figure, but that doesn't necessarily need to be his mother's fiancé."
Do you have a dog story to share? Email paige.freshwater@reachplc.com.
