what does ‘NTLDR is missing” mean

one of my children did something to my laptop and now all i have on the screen is the message NTLDR is missing press any key to restart…..pressing keys simply reprints the same message as does turning the machine off and back on again….i put in the recovery disc and it brings up the IBM thinkpad intro page and then the screen reverts to the same message again….what’s going on pls
k