Yes! They will have their own cash interest limit that matches whatever subscription plan you, as the registered contact, are on. This will be separate to any cash interest that you, as a Freetrade account holder, earn on your GIA, ISA, and SIPP.
So if you are a Basic plan customer, your child will earn 1% AER on up to £1,000 uninvested cash in their Junior ISA.
If you are a Standard plan customer, your child will earn 2.5% AER on up to £2,000 uninvested cash in their Junior ISA.
If you are a Plus plan customer, your child will earn 3.5% AER on up to £3,000 uninvested cash in their Junior ISA.
Cash interest will be paid into their Junior ISA on the 11th working day of every month. Like any other money in a Junior ISA, it cannot be withdrawn before the child turns 18.