  Some of the small inner moons of Uranus have very closely-spaced orbits.
Multiple numerical studies have found that the moons Cressida and Desdemona,
within the Portia sub-group, are likely to collide in less than 100 Myr. The
subsequent discovery of three new moons (Cupid, Perdita, and Mab) made the
system even more crowded. In particular, it has been suggested that the Belinda
group (Cupid, Belinda, and Perdita) will become unstable in as little as 10$^5$
years. Here we revisit the issue of the stability of the inner moons of Uranus
using updated orbital elements and considering tidal dissipation. We find that
the Belinda group can be stable on $10^8$-year timescales due to an orbital
resonance between Belinda and Perdita. We find that tidal evolution cannot form
the Belinda-Perdita resonance, but convergent migration could contribute to the
long-term instability of the Portia group. We propose that Belinda captured
Perdita into the resonance during the last episode of disruption and
re-accretion among the inner moons, possibly hundreds of Myr ago.
