Hmmm....so i guess the answer has been made to the question. I am now putting all the answers which u people and me gave, so that its easier for anyone to look for the answer.
Here is the list:
1) i don't think they could have apparated because of the fidellus charm. and i also think its becuz she didn't have her wand (anmol7)
2) Many houses are enchanted to stop people apparating in and out, to keep intruders out.
Mr Weasley doesn't apparate to the ministry from within the house, he leaves the house to do so.
Hogwarts is bewitched to keep intruders out too, houses are usually charmed so people can't apparate in and out... (Mkerai)
3) Well my theory...
Does anyone remember, in the Order of the Phoenix when the Death eaters were fighting the order and everyone was really scared and Dumbledore arrived... (And Harry said the great "we were saved" .. I love dumbledore so much!!! RIP)... Well then, Dumbledore used an anti-disapparation charm which ensured that none of the death eaters escaped that area. Voldemort being one of the greatest wizards alive (now dead) would definitely have had the sense to use something like that i'm guessing? Otherwise he wouldn't have got them ever 😳 😆 (Naughty_n_nice)
4) My answer is very short and i would love to say: very simple. It is written in HP very clearly that u need to have these things to apparate: Destination, deliberation and another thing i forgot...😆😆😆
My point is that apparation isnt a very easy magic. Or otherwise hogwarts could teach how to apparate at very low age. But see, they teach apparation when the children becomes adult, that is when they become 17 years old...my point is that doing apparation is a complicated and hard thing...not as easy as it seems...
And lily was under stress...ofcourse she will be...everyone in the world will faint when they see Lord Voldemort😆😆 So Lily was also very afraid...
Therefore she wasnt able to apparate even if she wants to...
And like u people said it might also be possible that there house was apparation-free, or Voldy have something to stop people from apparating... (stranger@mirror)
Hmmm....so i think theres totally FOUR theories to this critical questions...😆😳
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