If the forks and spoons are bending on the way to his mouth, then there are a number of possibilities.
These may be very, very cheap forks, and he should buy some new ones.
There may be some trickery going on. That is, someone is bending forks on the sly, and lying about it. It's impossible to guess who might be doing this and why without more information.
The third possibility is that something supernatural is bending the forks. This is very unlikely, but if it's true, your grandson is eligible for a million dollar prize. To win the prize, the bending needs to be observed by someone trained to look for the various sneaky ways that people bend forks and spoons. If there is trickery, the observer will reveal it, and then your family has to move on from there.
If the observer cannot explain what is going on, then your family gets a million bucks. (There are a number of steps you need to go through, but we'll cross that bridge when we get to it.)