Cracks between sidewalk and house.?

I would be mostly concerned about the water getting in. After repairing much water damage personally, you need to put that foremost. Use some type of sealent in the crack that is exterior grade and make sure the water sheds away from the house. Sealing off the the water and light from getting to the weeds should do them in. Water damage can do incredible things from all types of mould to structural damage so don't wait! Good luck!!

From your description, I doubt that it is a copperhead but your area is an interesting one for copperheads; it's where the northern, southern, and broadbanded copperheads come together. To be sure, either post or email the photo. Just tell your five-year old not to put his/her hand where he/she can't see it and not to touch any snakes. Yeah, I know. The chances are that your warning will be forgotten in two minutes. However, the chances are that 1) the snake is non-venomous and that 2) a copperhead bite, especially from a baby is almost never life-threatening. I know, I know. You want better odds.

You can also pour a small amount of diluted bleach in the cracks. This will inhibit anything from growing because the soil will be contaminated. Then seal away.

Vinegar will kill the weeds between your sidewalk cracks , it does work , when they become dead , pull them out . It may smell a little but its the cheap way to go and it works .

If it is not needed, I'd have it removed completely along with the trees.

you need to use a self leveling caulking. It will expand well with climate changes, it comes in a big tube. works well.

that is because tha sidewalk is exspandin cause of tha heat