We study the boundary behaviour of solutions to second order parabolic linear equations in moving domains. Our main result is a higher order boundary Harnack inequality in C1 and Ck, α domains, providing that the quotient of two solutions vanishing on the boundary of the domain is as smooth as the boundary.
As a consequence of our result, we provide a new proof of higher order regularity of the free boundary in the parabolic obstacle problem.
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