  Nuclear spin registers in the vicinity of electron spins in solid state
systems offer a powerful resource to address the challenge of scalability in
quantum architectures. We investigate here the properties of $^{29}$Si nuclear
spins surrounding donor atoms in silicon, and consider the use of such spins,
combined with the donor nuclear spin, as a quantum register coupled to the
donor electron spin. We find the coherence of the nearby $^{29}$Si nuclear
spins is effectively protected by the presence of the donor electron spin,
leading to coherence times in the second timescale - over two orders of
magnitude greater than the coherence times in bulk silicon. We theoretically
investigate the use of such a register for quantum error correction, including
methods to protect nuclear spins from the ionisation/neutralisation of the
donor, which is necessary for the re-initialisation of the ancillae qubits.
This provides a route for multi-round quantum error correction using donors in
silicon.
