Hi. We're going away soon with family, including our nearly 3 year old grandchild. Is there such a thing as a safety lock you can put on patio doors that lead out to the balcony? ( I know, I'm a worrier!). The wee guy is an explorer and I am a heavy sleeper. It's also a high hotel. We want to be able to have the wee one in our room a few nights to give his parents a break.... the irony is I never worried about such things when his dad was a toddler and he was fine...😂! Any ideas? Thank you!