No, not all rocky planets have gas giants in their respective solar systems. The presence of gas giants, also known as giant planets, in a solar system is not a requirement for the formation of rocky planets. The formation and composition of planets in a solar system depend on various factors, including the initial conditions of the protoplanetary disk, the available materials, and the dynamics of planetary formation.
In our own solar system, the four inner planets—Mercury, Venus, Earth, and Mars—are rocky or terrestrial planets and do not have gas giants in close proximity. However, the outer region of our solar system is populated by gas giants, such as Jupiter and Saturn.
In other solar systems, known as exoplanetary systems, the presence of gas giants can vary. Some exoplanetary systems have been discovered with gas giants, while others have been found to be predominantly composed of rocky or terrestrial planets. The presence or absence of gas giants in a given system is influenced by the specific conditions and processes that occur during planetary formation.