question about remote...

... for those who know more than me.
Left my 2001 Disco2 on the drive while I was away for a week. Upon return, my key wouldn't open it. Battery, I thought. But same result with the spare key.
Opened driver's door manually with the key. Alarm went off but remote was working again, so I could switch off the alarm, after which it's working fine again.
Knowing that teenage daughter could have accessed the key in my absence, does this suggest she's tampered with it? Or does the remote cease to work if not operated for a number of days?
Any clues folks?

All standard stuff, the system goes to sleep after a couple of days or so. The waking up procudure is just what you did and unlock with the key first not the fob.
All the info is in the owners handbook.

Must get my hands on an owners manual for mine. I have a 01 ES that goes to sleep after about 12hrs. Pain in the ass really

The owners handbook only states...

NOTE: If the handset does not operate after the
vehicle has been parked for a long period,
unlock the driver's door with the key and then
try again.

And download your copy of the handbook TOPIx - TOPIx

I got a 94 disco 300tdi, when bought had no remote key fob, i have heard i can but 1 for around £30 and programme it to mine, Is It Worth it. deos anyone know if this is true about programming it to mine. P.s. alarm works as i found out, central locking works with indicators flashing...

You must have a single button fob and that's user programable and it's simple, just search the forum for the info.