This is my first larger furniture piece and definitely made lots of mistakes between design and execution.
It’s all cherry and designed so one end is a right angle and the top shelf if shallower to fit into the fireplace.
My main power tool is a track saw but I did have access to a wood shop for a day to mill some rougher boards. Otherwise I used hand tools to finish the rest.
I used dowels and track saw cut grooves/rabbets for most of the joinery.
It was a mistake to make it in two sections instead of just having the sides be one larger piece. I also went too aggressive with my new router. Should have made much smaller bevels.
Is it removable? Like when it’s winter you can take the bookshelf out and use the fireplace, or is this permanent?
It just slides in, although we may mount it somehow to avoid children moving it around.
I'm guessing your first?
Secure it. Children are nightmarish levels of creative when it comes to choices that are dangerous to them.
A quick example...
My kids like to watch the animals out back. Deer, birds, bobcats, foxes, etc. Upstairs, the windows are a bit lower. Downstairs, they are a bit higher.
My daughter would stand on a chair, or use a stepstool, or even stand on the couch. She's big enough to not need any of those options anymore.
My son also uses the chair, stool, or couch, but he doesnt stop there. The exterior walls are pretty thick, so the interior sill is just shy of 6".
Your guess is correct, he uses the chair, stool, or couch to get onto the sill to look at them. We tried to block access with plants... He moved them or knocked them off. When I put some boards up, he stood on top of the dining room table. He then thought the chandelier made a really neat swing. He is incredibly opportunistic, and will do this when I'm working in my office and mom is cooking or in the bathroom. The moment he realizes he has a solid set of moments, he is off to commit acts of preschool terrorism.
I highly recommend securing it.
Also, congrats!