naturalized British citizen with third country parent

[wabird]

Pls advice,
I have lived in Uk since 2000. My limited stay visa which is due to expire in August 2012 was cancelled in December 2010 while I was on holiday in my home country. I managed to come back to the UK in late 2011 with my two daughters, 7yrs and 5yrs. The 7yr old is a naturalized british citizen. We were allowed in at Heathrow but the immigration officer withheld the passports. Its been more than 6 months now with no reply from HO. Yesterday they wrote to me asking me to give reasons why I should stay in UK. Pls advice on the best approach on how i can write a successful application

[geriatrix]

Please don't make multiple posts on the same topic.