I met the "other" dog sitter...

I have a long term client who I have dog sat for about five years now.They continually book us so often that they are our main client. No complaints, they treat us very well and often tip about $200-$500. At a Christmas party this weekend, we met the other dog sitter who lives right across the street. They book her when we are not available. I found out she charges twenty more dollars a day and doesn't always even stay there during the day because she visits other clients. Meanwhile, I'm charging less and staying there all day because I work from home. I don't want to bring up the rate comparison to them, but would like to raise my rates... I don't think a twenty dollar jump would be fair, but any advice on how to incrementally raise it for 2025? I'm pretty sure I'm below market value because I am coming from a few years off and didn't know what people were charging. Ibuprofen also love these clients and don't want to lose them.