  We investigate the effects of the evolutionary processes in the internal
magnetic structure of two interplanetary coronal mass ejections (ICMEs)
detected in situ between 2020 November 29 and December 1 by Parker Solar Probe
(PSP). The sources of the ICMEs were observed remotely at the Sun in EUV and
subsequently tracked to their coronal counterparts in white light. This period
is of particular interest to the community since it has been identified as the
first widespread solar energetic particle event of Solar Cycle 25. The
distribution of various solar and heliospheric-dedicated spacecraft throughout
the inner heliosphere during PSP observations of these large-scale magnetic
structures enables a comprehensive analysis of the internal evolution and
topology of such structures. By assembling different models and techniques, we
identify the signatures of interaction between the two consecutive ICMEs and
the implications for their internal structure. We use multispacecraft
observations in combination with a remote-sensing forward modeling technique,
numerical propagation models, and in-situ reconstruction techniques. The
outcome, from the full reconciliations, demonstrates that the two CMEs are
interacting in the vicinity of PSP. Thus, we identify the in-situ observations
based on the physical processes that are associated with the interaction and
collision of both CMEs. We also expand the flux rope modeling and in-situ
reconstruction technique to incorporate the aging and expansion effects in a
distorted internal magnetic structure and explore the implications of both
effects in the magnetic configuration of the ICMEs.
