How many kids stay in the room DAMIEN TRACHSEL checked in on Sep 21, 2010?
CREATE TABLE rooms (
    roomid text,
    roomname text,
    beds number,
    bedtype text,
    maxoccupancy number,
    baseprice number,
    decor text
)

CREATE TABLE reservations (
    code number,
    room text,
    checkin text,
    checkout text,
    rate number,
    lastname text,
    firstname text,
    adults number,
    kids number
)
SELECT kids FROM reservations WHERE checkin = "2010-09-21" AND firstname = "DAMIEN" AND lastname = "TRACHSEL"
Below are sql tables schemas paired with instruction that describes a task. Using valid SQLite, write a response that appropriately completes the request for the provided tables. ### Instruction: How many kids stay in the room DAMIEN TRACHSEL checked in on Sep 21, 2010? ### Input: CREATE TABLE rooms (
    roomid text,
    roomname text,
    beds number,
    bedtype text,
    maxoccupancy number,
    baseprice number,
    decor text
)

CREATE TABLE reservations (
    code number,
    room text,
    checkin text,
    checkout text,
    rate number,
    lastname text,
    firstname text,
    adults number,
    kids number
) ### Response: SELECT kids FROM reservations WHERE checkin = "2010-09-21" AND firstname = "DAMIEN" AND lastname = "TRACHSEL"