Naps!

So my little one is a cat napper and overall not a great sleeper recently she’s 18 weeks old. So basically at night goes to bed between 7-8. Will sleep a few hours dream feed her and then after like 1 is up every 2 hours to eat then wakes at 8 ish in the morning. And for naps she will take like a 30-50 minute nAp around 10 up for a while then around 1230 gets tired and grouchy and wants to sleep so usually I rock her to sleep in my arms and then I lay with her so that she takes a longer nap and usually when i do this and I just lie next to her she will sleep 1.5 hours. I’m just wondering do you think it’s a bad habit napping with her in the day so she naps longer. Should I just be letting her cat nap all day until she figures out how to nap longer? The reason I try to extend naps is she just seems happier overall after a nice long nap.

Any advice would be appreciated!