Changing key children too often????

[Mrs Frog]

My boss in my job of 4 months has switched 3 of my key children over the last few weeks,I am really upset,one child has just had a new sibling,one has just had a little brother start at the same nursery and the other starts school in september,I have loved doing their learning journeys and building up a realationship with them and now my boss wants to switch another one for a younger child and this child has English as a second language and I have turned round and said "No" as I am so upset,I know their next steps,plan for their next milestones and then I get a note saying please give XXXXXX child to a colleague,am I right to be upset??? She awitches other children too not just mine