Another set of PlayStation Plus free games for this month will be added to the Instant Game Collection early this week.

According to the post from Senior Community Specialist, Kristine Steimer on PlayStation Blog, "Brothers: A Tale of Two Sons" will enter IGC tomorrow, January 21 as part of the PlayStation Plus free games for January in the US.

"Brothers: A Tale of Two Sons" is a PlayStation 3 title which "follows the journey of two brothers on an quest to find a cure for their dying father," as posted on Gamezone. Furthermore, the description for the game reads, "It features a unique control system in which each brother is assigned to a different thumbstick."

As for the gameplay of this PlayStation Plus free game, players must use both the brothers cooperatively to solve puzzles and explore the environments surrounding them.

Aside from this PS3 title, other PlayStation Plus free games will be added to Sony's Instant Game Collection for US gamers tomorrow. Accordingly, PS Vita game, Worms: Battle Island will be available for free for PS Plus members. The game, as described on PS Blog page:

Battle up to three other players offline or online on one of six landscape themes, using one of forty classic Worms weapons or some of your own creation in the weapons factory. With sixty single player challenges, five game modes, a powerful level editor and a massive selection of ways to personalize your worm army and customize your game experience, it's a package sky-high on entertainment!

Moreover, Sony is offering discounts for its number of games. As part of its PS Vita Play Sale, OlliOlli is available only for $10.39. Music games such as "Rock Band Blitz"and "Kickbeat" are also available for discounted price.

Gamers will be able to download PlayStation Plus free games "Brothers: A Tale of Two Sons" and "Worms: Battle Island after the PS Store gets updated tomorrow, January 21.