assalamu alaikum
mashallah
my nephew who is 5 always asks me these kind of questions, we always have a 'heart to heart' when i pik him up from school ;D
anyway alhamdulillah he always asks me thez kind of questions, the first he asked was 'who's allah?' an i told im that allah made us all, he's the greatest who knows everything u do, thats why we shud say thank u oh allah everyday becoz he gives us books, toys and cars, (and all other things kids are into!) and you can talk to allah about anyting n he'll listen, and if u want something, always ask allah for it, and he'll give it to u. so he listened quite carefully and then the next day it was raining so he goz 'why duz it rain' and then i told him that allah sends the rain because flowers need rain to grow, n the flowers are so beautiful rent there (n like a kid he agreed with me lol) and if it didnt rain then itd be really hot like it is in pakistan
and everyone wud get really thirsty, so rains very good. then he started praising rain ;D subhanallah, but lyk this, he always now asks questions, n he has a mch better undrstanding of who Allah is, inshallah his wish to seek knowledge will continue! along with ur niece arwa sis, and everyone else's children. inshallah. but a miracle is the facct that after our talks on allah and how beautiful everything is, my nephew now sees the kaabah (wich i told im was the house of allah where we need to pray towards, allah doesnt live there because allahs everywhere, but he wants us 2 pray towards there - its really nice isnt it?n he agreed again lol) when he sees it, he wants to go to 'hajj' and 'umrah' and when he's crying he starts sayin he wants to go to Allah so subhanallah it tkes effect n has a difference if we explain to them in a 'kiddy' fashion/ never brush them off wen it cms to questions regrding islam. we all inshallah want them to be aalims/aalimas dont we!!
but one thing they really get xcited about is if u say 'when u want a toy or sumthing, ask allah for it' and always tell them about jannat and jahannum, that heavens for the good people, n if u listen to ur mum n dad, n be good, n share ur toys with the lil ones, youll go there, n hells for those people who are rude, and swear alot, and dont eat their dinner, and fight with others.
inshallah hope it is of some help
walaikumussalam