  We investigate the intermediate-age asymptotic giant branch stellar
population of two Local Group dwarf irregular galaxies to characterize their
carbon star population in near-infrared (IR). Our work is based on J and K-band
SOFI near-IR photometry complemented with optical ground based and HST
photometry. We show that near-IR photometry is a very powerful tool for carbon
star detection. We recovered two out of three previously-known carbon stars in
DDO 210 and discovered six additional objects in this galaxy which have optical
and near-IR colors consistent with carbon giants. This brings the total number
of bona-fide C-star candidates in DDO 210 to nine. We detected a large
population of C-star candidates in SagDIG, 18 of which were previously
identified in Demers & Battinelli (2002) and Cook (1987), and six new bona-fide
carbon stars. We present their optical and near-IR colors and use their
luminosity function to put constraints on the star formation history (SFH) in
this dwarf irregular galaxy.
