  Observations have confirmed the existence of multiple-planet systems
containing a hot Jupiter and smaller planetary companions. Examples include
WASP-47, Kepler-730, and TOI-1130. We examine the plausibility of forming such
systems in situ using $N$-body simulations that include a realistic treatment
of collisions, an evolving protoplanetary disc and eccentricity/inclination
damping of planetary embryos. Initial conditions are constructed using two
different models for the core of the giant planet: a 'seed-model' and an
'equal-mass-model'. The former has a more massive protoplanet placed among
multiple small embryos in a compact configuration. The latter consists only of
equal-mass embryos. Simulations of the seed-model lead to the formation of
systems containing a hot Jupiter and super-Earths. The evolution consistently
follows four distinct phases: early giant impacts; runaway gas accretion onto
the seed protoplanet; disc damping-dominated evolution of the embryos orbiting
exterior to the giant; a late chaotic phase after dispersal of the gas disc.
Approximately 1% of the equal-mass simulations form a giant and follow the same
four-phase evolution. Synthetic transit observations of the equal-mass
simulations provide an occurrence rate of 0.26% for systems containing a hot
Jupiter and an inner super-Earth, similar to the 0.2% occurrence rate from
actual transit surveys, but simulated hot Jupiters are rarely detected as
single transiting planets, in disagreement with observations. A subset of our
simulations form two close-in giants, similar to the WASP-148 system. The
scenario explored here provides a viable pathway for forming systems with
unusual architectures, but does not apply to the majority of hot Jupiters.
