As you are shifted to Islamabad. You test your driving skills at hills in Margallas (Upto Pir Sohawa)... If you can drive there... you can drive in Galyat area.
Yes its OK for an infant... no problem... but take light warm clothes for kid..
If you reside there for a night.. then it would be good...
Always remember.. don't travel in hills in night... waisay in night there is all ok for security.
Route is Islamabad-Murree approx 50 Km... Use left (old murree road) it separate from 17 Meel...
Actually there are two roads... One is Murree Expressway... Don't follow this road...
Use old murree road...
from murree (sunny bank chowk) go to Murree Mall road.... spend some time there go pindi or kashmir point if you want to see murree..
After this... come back to sunny bank and go to Nathia Gali Road...
Nathia Gali is approx 30-35 km from Murreee.
Ayubia is name of a national park that spreads from Changla Gali to Bara Gali or so...
But where ayubia chair lift is present.. people say it ayubia....
Going on nathia gali road from murree after 20 km you reach the Kuza Gali and turn right for Ayubia...
Ayubia chair lift is 3km from here.
Enjoy there chair lift...
You can trek there also... pipeline trek..
https://www.pakwheels.com/forums/road-trips-vacations/167038-guide-galyat-area
and then come back to Kuza gali again... after that you drive to Nathia Gali... excellant views on whole road.. enjoy nathia gali... some 10-15 km from kuza gali...
Enjoy Nathia gali area... watch Mount Meeran Jani from there....
and then i recommend you that you go to abbotabad from nathia gali...
Nathia Gali to Abbotabad 30 km
From Abbotabad you can back to islamabad via haripur, havelian, taxila... and then islamabad.
From Murree you can go also to New Murree Patriata.. beautiful chairlift and cable car is there.
One night stay somewhere is recommended...
Don't drive in night..
Entry of park is free... chair lift charges might be somewhere 100-200 (infant free)
Thanks