To run a job even if its previous job in the sequence is failed you need to go to the TRIGGER tab of that particular job activity in the sequence itself.
There you will find three fields:
Name: This is the name of the next link (link goin to the next job, e.g. for job activity 1 link name will be the link goin to job activity 2).
Expression Type: This will allow you to trigger your next job activity based on the status you want. For example, if in case job 1 fails and you want to run the job 2 and job 3 then go to trigger properties of the job 1 and select expression type as "Failed - (Conditional)". This way you can run your job 2 even if your job 1 is aborted. There are many other options available.
Expression: This is editable for some options. Like for expression type "Failed" you can not change this field.
I think this will solve your problem.