MYSQL Triggers syntax
I guess you want to either insert a new row with the counter status_likes = 1 or incresase it by 1 when a row with status_id already exists. If there is a UNIQUE constraint on member_status_like_count (status_id), you can use INSERT ... ON DUPLICATE KEY UPDATE:

CREATE TRIGGER member_status_likes__AFTER_INSERT__UPSERT__like_count
AFTER INSERT ON member_status_likes 
FOR EACH ROW 
  INSERT INTO member_status_like_count 
      (status_id, status_likes) 
  VALUES
      (NEW.status_id, 1)
  ON DUPLICATE KEY UPDATE
      status_likes = status_likes + 1 ;